Malicious PDF — malware analysis report

Static analysis result for SHA-256 341f8fe9a5009904…

MALICIOUS

PDF

72.8 KB Created: 2021-09-19 12:04:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: fd42def1f24c06d5e9b02c8e9c41f33e SHA-1: ec96a146f613092544611e1c803221ad7b3b64bb SHA-256: 341f8fe9a500990420eeca46098cea7f61cbde7458c3598a7362f07492b06be4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as a malicious PDF by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to potentially compromised or disposable hosting, suggesting a phishing or malware distribution scheme. The presence of multiple PDF link farm heuristics reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://dent-pro.cz/pic/file/lozukologij.pdf In PDF document text
    • http://builderall.info/userfiles/file/98380446318.pdfIn PDF document text
    • http://373113.linker.tw/files/kutisikat.pdfIn PDF document text
    • http://noxsun.com/jingkelun/userfiles/files/20210915220601.pdfIn PDF document text
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/75c5de7ee57a3b40a9493932e59c0a42/2920738316.pdfIn PDF document text
    • http://galettedesrois.hu/userfiles/file/tetok.pdfIn PDF document text
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161454fb3f0607---worut.pdfIn PDF document text
    • https://testgit.begurholidays.com/uploads/userfiles/files/27676111113.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144762b38fb6---7141038781.pdfIn PDF document text
    • http://jlsxjy.com/right/UploadFile/file///2021091803014173499.pdfIn PDF document text
    • http://koppeika.ru/userfiles/file/pojuzulal.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/16145fe73577f6---gaxiwaki.pdfIn PDF document text
    • http://okna-kurska.ru/page_edit/_samples/userfiles/files/rofivugijifesexawitosowi.pdfIn PDF document text
    • http://mitroc.com/userfiles/file/misemupolajo.pdfIn PDF document text
    • http://imaginove.eu/data/Files/wedesofokowiliji.pdfIn PDF document text
    • http://www.ecostroyservis.ru/File/89911725141.pdfIn PDF document text
    • http://alajwakh.com/uploaded_files/userfiles/files/nezetofujimibeseradakat.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b348c4ae2d---6319117502.pdfIn PDF document text
    • http://geobigoni.it/userfiles/files/lopaxaxew.pdfIn PDF document text
    • http://nhasachthunam.com/upload/files/68419110048.pdfIn PDF document text
    • https://mamalight.net/business_school/uploads/file/61127959205.pdfIn PDF document text
    • https://ecableapp.com/FCKeditor/FCKimgUpload/file/46651566265.pdfIn PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/41b98033e2ad512b7bca8a2ac980c3f6/220164982.pdfIn PDF document text
    • http://nhuaduongnhapkhauaz.info/upload/files/vopanimokovokepukoli.pdfIn PDF document text
    • https://artedelvalle.cl/gal/files/file/benab.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=best+escape+room+games+iosPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bb71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB71 16104 bytes
SHA-256: ef5882fde3e828d175faadf02becaae2c5dc5d072d64e2b7ef7758aa16f327f1
font_01_sfnt_off0000e4af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4AF 10620 bytes
SHA-256: f74fae640efbfb2717f991ff03e1ef8304cdd44a35e713b0173946d5c8b399f9
font_02_sfnt_off0000fd11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD11 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1